Gamma Apodis

Gamma Apodis is a star in the southern circumpolar constellation of Apus. Its identifier is a Bayer designation that is Latinized from γ Apodis, and is abbreviated Gam Aps or γ Aps, respectively. It is visible to the naked eye with an apparent visual magnitude of 3.86.^[3] From parallax measurements, the distance to this star can be estimated as 153 light-years (47 pc). The star is receding with a heliocentric radial velocity of +5.7 km/s.^[3]

γ Apodis

Location of γ Apodis (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Apus[1]
Right ascension	16h 33m 27.08252s[2]
Declination	−78° 53′ 49.7334″[2]
Apparent magnitude (V)	3.86[3]
Characteristics
Evolutionary stage	red clump[4]
Spectral type	G9 III[3]
U−B color index	+0.62[5]
B−V color index	+0.91[5]
Astrometry
Radial velocity (Rv)	+5.7[3] km/s
Proper motion (μ)	RA: −125.575 mas/yr[2] Dec.: −78.212 mas/yr[2]
Parallax (π)	21.3033±0.1523 mas[2]
Distance	153 ± 1 ly (46.9 ± 0.3 pc)
Absolute magnitude (MV)	+0.41[6]
Details
Mass	2.32[7] M☉
Radius	10.293[8] R☉
Surface gravity (log g)	3.074±0.081[9] cgs
Temperature	5,151±50[9] K
Metallicity [Fe/H]	0.090±0.042[9] dex
Rotational velocity (v sin i)	5.016±0.417[9] km/s
Age	2.67[7] Gyr
Other designations
γ Aps, γ Apodis, CPD−78°1103, FK5 611, GJ 626.1, GJ 9563, HD 147675, HIP 81065, HR 6102, SAO 257407[10]
Database references
SIMBAD	data

A stellar classification of G9 III^[3] identifies Gamma Apodis as a giant star in the later stages of its evolution. This is a red clump giant, which means it is on the horizontal branch and is generating energy through core helium fusion.^[4] The star has 2.3^[7] times the mass of the Sun and has expanded to 10.3^[8] times the Sun's radius. It is 2.7^[7] billion years old and is spinning with a projected rotational velocity of 5 km/s.^[9] This is an active X-ray source with a luminosity of 1.607×10³⁰ erg s⁻¹, making it one of the 100 strongest stellar X-ray sources within 50 parsecs of the Sun.^[11]

Naming

In Chinese caused by adaptation of the European southern hemisphere constellations into the Chinese system, 異雀 (Yì Què), meaning Exotic Bird, refers to an asterism consisting of γ Apodis, ζ Apodis, ι Apodis, β Apodis, δ Octantis, δ¹ Apodis, η Apodis, α Apodis and ε Apodis. Consequently, γ Apodis itself is known as 異雀四 (Yì Què sì, English: the Fourth Star of Exotic Bird).^[12]